A rollover on Route 2 in the westbound lane Wednesday might have been the cause of a four-car accident that occurred moments later, close to the same location, and involved an Athol Fire Department ambulance, according to state police spokesman David Procopio.

No patient was in the ambulance at the time of the accident, he said.

State police received a call around 3:40 p.m. of an accident slightly west of the Abbott Avenue exit, Mr. Procopio said.

Four minutes later, one of the troopers who responded called in a second crash that he said occurred as a result of the first crash.

The first crash involved one vehicle: A 2005 Chevrolet Aveo driven by Mary Brigham, 54, of Westminster who was transported to UMass Memorial Medical Center  University Campus in Worcester for non-life-threatening injuries, he said.

According to a preliminary statement from a witness, Ms. Brigham lost control of her car when a car in front of her slowed down to allow another vehicle to merge onto Route 2, Mr. Procopio said.

Her car swerved to avoid striking the woman who slowed down, he said.

Ms. Brigham did not hit the car that slowed down, but she lost control when she swerved and rolled her vehicle over into the trees and was trapped, he said. The Leominster Fire Department had to extricate her from her car. She was wearing a seat belt, he said.

No one was found at fault, and no citations were issued in that crash, he said.

Details are not available on the second crash, he said, which is still under investigation.

In that crash, an Athol Fire Department ambulance operated by Firefighter Arthur Shepardson Jr., 47, of Athol was involved in a four-car accident near the same location as the first. Athol Firefighter Kevin Kaczmarczyk, 35, was a passenger in the ambulance.

The other vehicles involved were a 2006 Toyota Rav4 driven by Benjamin J. Mbwambo, 41, of Leominster; a 1998 Subaru Legacy station wagon driven by a 32-year-old Princeton woman, transporting her 31-year-old husband and two sons, ages 2 and 4; and a 1999 Oldsmobile driven by a 33-year-old Gardner man.

The family was not injured, but the others involved were transported and treated for minor injuries.

Contact Paula Owen at powen@telegram.com. Follow her on Twitter @PaulaOwenTG.

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